The invention relates to bone grafts and more particularly, to bone grafts useful for spinal fusion. The invention provides a composite bone graft for implantation in a patient, and methods of making and using the composite bone graft. The composite bone graft contains two or more distinct bone portions where the bone portions are connected. The bone portions are preferably self-locking, interlocking, and/or connected by at least one mechanical connector, including for example, a bone pin. One or more of the bone portions may be demineralized, and may also be continuous or discontinuous. The composite bone graft may include one or more textured surfaces, preferably including a plurality of closely spaced protusions. The composite bone graft is useful for repairing bone defects caused by congenital anomaly, disease, or trauma, and is particularly useful for spinal fusions. The composite bone graft can be appropriately sized for any application and can be used to replace traditional non-bone prosthetic implants. The composite bone graft promotes the growth of patient bone at an implantation site by promoting osteoinductivity and cellularization, provides added stability and mechanical strength, and does not shift, extrude or rotate, after implantation.
In the field of prosthetic implants, materials often used include bone grafts and implants produced from non-bone materials, including for example stainless steel, titanium and plastics. The choice of whether to use a bone or a non-bone implant often depends on the clinical indication, implant site, whether the implant is load-bearing, and the size of the implant needed.
Prior to the present invention, the use of bone grafts versus non-bone prosthetic implants to for example, support and fuse together adjacent vertebrae, has been limited in part by the physical size of a cortical bone graft. Interbody bone grafting involves the problem of strength. Strong cortical bone (the outer layer) is required as a strut in the interbody position to prevent collapse of the disc space while healing occurs. For example, cortical bone obtained from a cadaver source fashioned into struts, is not wide enough for optimum load bearing. This natural limitation often excludes the use of a bone graft product.
The success or failure of a bone graft further depends on whether the bone graft remains at the implant site, is cellularized, and whether it can withstand the mechanical load. In spinal surgery, there are two primary indications for use of allograft bone: (1) when there is insufficient available autograft bone, and (2) in spinal fusion procedures when a structural element in needed. Typically, bone grafts are affixed at an implant site by fusion. Bone grafts for spinal applications often fail because they are extruded from the implantation site due to shifting, rotation, and slippage of the graft, are not cellularized, or fail mechanically.
The invention enables the use of bone grafts for applications normally suited for only non-bone prosthetic implants. The invention solves the problem of graft failure by providing a composite bone graft which can be appropriately sized for any application out of for example, strong cortical bone; promotes the ingrowth of patient bone at an implantation site by promoting osteoinductivity and cellularization; provides added stability and mechanical strength; and does not shift, extrude or rotate; after implantation.
The present invention is directed to a composite bone graft for repairing bone defects caused by congenital anomaly, disease, or trauma, including for example, for restoring vertical support of the posterior and/or anterior colunm. The present composite bone grafts can be used as structural grafts placed posteriorly in the spine as interbody grafts or as strut grafts spanning multiple segments. Posterior composite bone grafts can be used to supplement autologous bone for spinal fusions in patients who lack sufficient host bone and to avoid significant donor site morbidity. The present composite bone grafts can be used for applications normally suited for only non-bone prosthetic implants because the composite bone graft can be appropriately sized for any application and has adequate mechanical strength.
The invention provides a composite bone graft including a plurality of bone portions layered to form a graft unit, and one or more biocompatible connectors for holding together the graft unit.
The invention also provides a composite bone graft including two or more distinct bone portions, and one or more biocompatible connectors, where the biocompatible connectors hold together the two or more bone portions to form the composite bone graft.
The present invention provides a composite bone graft including two or more connected, distinct bone portions.
The present invention provides a composite bone graft including three or more connected, distinct bone portions.
The present invention provides a composite bone graft including three or more connected, distinct cortical bone portions.
The present invention provides a composite bone graft including one or more horizontally disposed channels provided through the composite bone graft perpendicular to the interfaces of the bone portions.
The present invention also provides a composite bone graft including one or more vertically disposed channels provided through the composite bone graft parallel to the interfaces of the bone portions.
The present invention further provides a composite bone graft including one or more horizontally disposed channels and vertically disposed channels where the one or more channels includes one or more therapeutically beneficial substances.
The invention further provides a composite bone graft including two or more connected bone portions, where the bone portions can include cortical bone and cancellous bone.
The invention also provides a composite bone graft, including a first bone portion, a second bone portion, a third bone portion, the first, second and third bone portions are disposed one on the other (ie. layered) to form a graft unit; and one or more biocompatible connectors for holding together the graft unit.
The invention provides a composite bone graft, including a first cortical bone portion, a second cortical bone portion, a cancellous bone portion disposed between the first cortical bone portion and the second cortical bone portion to form a graft unit, and one or more biocompatible connectors for holding together the graft unit.
The invention further provides a composite bone graft, including a first cortical bone portion, a second cortical bone portion provided on the first cortical bone portion to form a graft unit; and one or more biocompatible connectors for holding together the graft unit.
The invention provides a composite bone graft, including a plurality of layered cortical bone portions forming a graft unit, and one or more biocompatible connectors for holding together the graft unit.
The invention provides a composite bone graft, including a plurality of layered bone portions forming a graft unit, and one or more biocompatible connectors for holding together the graft unit.
The invention also provides a composite bone graft, including a first bone portion, a second bone portion provided on the first bone portion to form a graft unit, and one or more biocompatible connectors for holding together the graft unit.
The invention provides a composite bone graft including a plurality of distinct bone portions, where one or more of the bone portions are demineralized.
The invention provides a composite bone graft including a plurality of distinct bone portions, where one or more of the bone portions are continuous or discontinuous.
The invention further provides a composite bone graft including a plurality of distinct bone portions where one or more of the bone portions include a discontinuous bone portion, the discontinuous bone portion including one or more therapeutically beneficial substances including but not limited to, for example, one or more of the following: osteoinductive substances, osteoconductive substances, and pharmaceutically active agents. Such therapeutically beneficial substances may optionally be provided with a carrier. Suitable osteoinductive substances include but are not limited to, for example, autograft bone; allograft bone; Grafton(trademark) produced by Osteotech; DynaGraft(trademark); demineralized cortical bone; demineralized cancellous bone; collagen including one or more growth factors including for example Novus(trademark) produced by Stryker Biotech; collagen including demineralized bone including for example DynaGraft(trademark); cancellous bone; cortical bone; OpteoForm(trademark) produced by the University of Florida; OsteoFill(trademark) produced by the University of Florida; and growth factors including for example, bone morphogenic protein, and transforming growth factor-xcex2. Suitable osteoconductive substances include but are not limited to, for example, hydroxyapitate; collagen; any biocompatible matrix material including for example, polymeric matrix materials, bioglass, bioceramics, resorbable Biomaterials; bioabsorbable polymers; a plastic matrix; stainless steel; titanium; cobalt-chromium-molybdenum alloy matrix; and substances including hydroxyapitate, including for example, Osteoset(trademark) produced by Wright Medical. Suitable pharmaceutically active agents include but are not limited to, for example, growth factors including for example bone growth factors including for example bone morphogenic protein, and transforming growth factor-xcex2, chemotherapeutic agents, anti-inflammatory agents, and antibiotics.
The invention also provides a composite bone graft, including a first cortical bone portion, a second cortical bone portion, a cancellous bone portion disposed between the first cortical bone portion and the second cortical bone portion to form a graft unit, and one or more biocompatible connectors for holding together the graft unit, where the cancellous bone portion is demineralized and discontinuous.
The invention provides a composite bone graft, including a first cortical bone portion, a second cortical bone portion, and a third cortical bone portion disposed between the first cortical bone portion and the second cortical bone portion to form a graft unit, and one or more biocompatible connectors for holding together the graft unit, where the third cortical bone portion is demineralized and discontinuous.
The invention provides a composite bone graft, including a first cortical bone portion, and a second cortical bone portion disposed apart from each other, and forming a graft unit, and one or more biocompatible mechanical connector for holding together the graft unit, where the first and second cortical bone portions are disposed separate from each other by the biocompatible mechanical connectors, thereby forming a substantially void central area.
The invention further provides a composite bone graft including a substantially void central area, where the substantially void central area further includes one or more therapeutically beneficial substances including but not limited to, for example, one or more of the following: osteoinductive substances, osteoconductive substances, and pharmaceutically active agents. Such therapeutically beneficial substances may optionally be provided with a carrier. Suitable osteoinductive substances include but are not limited to, for example, autograft bone; allograft bone; Grafton(trademark) produced by Osteotech; DynaGraft(trademark); demineralized cortical bone; demineralized cancellous bone; collagen including one or more growth factors including for example Novus(trademark) produced by Stryker Biotech; collagen including demineralized bone including for example DynaGraft(trademark); cancellous bone; cortical bone; OpteoForm(trademark) produced by the University of Florida; OsteoFill(trademark) produced by the University of Florida; and growth factors including for example bone morphogenic protein, and transforming growth factorxcex2. Suitable osteoconductive substances include but are not limited to, for example, hydroxyapitate; collagen; any biocompatible matrix material including for example, polymeric matrix materials, bioglass, bioceramics, resorbable Biomaterials; bioabsorbable polymers; a plastic matrix; stainless steel; titanium; cobalt-chromium-molybdenum alloy matrix; and substances including hydroxyapitate, including for example, Osteoset(trademark) produced by Wright Medical. Suitable pharmaceutically active agents include but are not limited to, for example, growth factors including for example bone growth factors including for example bone morphogenic protein, and transforming growth factorxcex2; chemotherapeutic agents; anti-inflammatory agents; and antibiotics. The material may be in any suitable form including for example, in the form of a solid, sponge, paste, powder, and/or gel.
The invention further provides a composite bone graft where the biocompatible connectors include one or more mechanical biocompatible connectors.
The invention provides a composite bone graft where the biocompatible connectors include a chemical biocompatible connector.
The invention further provides a composite bone graft where the mechanical biocompatible connectors include one or more pins.
The invention further provides a composite bone graft where the chemical biocompatible connectors include a biocompatible adhesive.
The invention provides a composite bone graft where one or more biocompatible connectors include one or more of the following: a mechanical connector and a chemical connector.
The invention also provides a composite bone graft where the mechanical biocompatible connectors include one or more of the following biocompatible materials: cortical bone; stainless steel; titanium; cobalt-chromium-molybdenum alloy; a bioceramic; a bioglass; a plastic of one or more of the following: nylon, polycarbonate, polypropylene, polyacetal, polyethylene, and polysulfone; and one or more bioabsorbable polymers.
The invention also provides a composite bone graft where the mechanical biocompatible connectors include cortical bone.
The invention provides a composite bone graft where the one or more pins include one or more cortical bone pins.
The invention provides a composite bone graft where the graft unit includes one or more through-holes configured to accomadate the one or more pins.
The invention further provides a composite bone graft where the through-holes are disposed perpendicular to interfaces of bone portions forming the graft unit.
The invention further provides a composite bone graft where the through-holes are disposed perpendicular to interfaces of for example, the first bone portion, the second bone portion, and the third bone portion, of the graft unit.
The invention provides a composite bone graft where the one or more pins and the one or more through-holes are configured to provide an interference fit for holding together the graft unit.
The invention also provides a composite bone graft where the one or more through-holes and the one or more pins are round and an inner diameter of a through-hole is smaller than a diameter of a pin, to provide an interference fit between the through-hole and the pin.
The invention further provides a composite bone graft where the one or more cortical bone pins include a plurality of vertical groves provided on a surface thereof.
The invention further provides a composite bone graft where the one or more cortical bone pins includes a roughened surface.
The invention provides a composite bone graft where the one or more cortical bone pins further includes a slot extending from one end of the bone pin.
The invention provides a composite bone graft where the one or more pins is threaded to provide a threaded engagement with the one or more through-holes.
The invention further provides a composite bone graft where the one or more pins is threaded and the one or more through-holes is threaded, to provide a threaded engagement between the one or more pins and the one or more through-holes.
The invention provides a composite bone graft where the one or more pins and the one or more through-holes are configured to provide a slidable connection, for example, to provide a composite bone graft including a substantially void central area.
The invention also provides a composite bone graft where a cross-section of the one or more pins includes a shape selected from the group including the following: round, ovoid, square, rectangular, triangular, pentagon, hexagon, and trapezoidal.
The invention further provides a composite bone graft including a plurality of plate-like cortical bone portions, the cortical bone portions layered to form a graft unit, the graft unit held together with one or more cortical bone pins.
The invention further provides a composite bone graft where the composite bone graft is a cortical cylinder.
The invention provides a composite bone graft including a graft unit having one or more through-holes configured to accommadate one or more pins, the graft unit including two or more bone portions layered to form the graft unit, and one or more pins for holding together the graft unit.
The invention further provides a composite bone graft, including a graft unit having one or more through-holes configured to accommadate one or more pins, the graft unit including a first plate-like cortical bone, a second plate-like cortical bone, a plate-like cancellous bone disposed between the first plate-like cortical bone and the second plate-like cortical bone to form the graft unit, and one or more cortical bone pins for holding together the graft unit.
The invention also provides a composite bone graft, including a graft unit having one or more through-holes configured to accommadate one or more pins, the graft unit including a first plate-like bone, a second plate-like bone provided on the first plate-like bone to form the graft unit, and one or more bone pins for holding together the graft unit.
The invention also provides a cervical composite bone graft, including a flattened curved wedge graft unit having one or more through-holes configured to accommadate one or more pins, the graft unit including two or more plate-like cortical bone portions layered to form the graft unit, and at least two bone pins for holding together the graft unit, where the graft unit includes a substantially centrally located through-hole. The diameter of the through-hole may be readily selected by one of ordinary skill in the art without undue experimentation depending upon the particular application; for example, the diameter of the through-hole may be from about 2.0 mm-4.0 mm; preferably 2.5 mm-3.0 mm; and more preferably 3.0 mm.
The invention also provides a composite bone graft where the one or more through-holes are disposed perpendicular to interfaces of plate-like bones of the graft unit.
The invention provides a composite bone graft where the composite bone graft is a parallelepiped; a parallel block; a square block; a trapezoid wedge; a cylinder; a tapered cylinder; a cervical wedge (flattened curved wedge); an ovoid wedge (anterior lumbar wedge graft) and a polyhedron.
The invention further provides a composite bone graft where the composite bone graft is a polyhedron including six planer surfaces.
The invention provides a composite bone graft where the composite bone graft further includes one or more textured surfaces.
The invention also provides a composite bone graft where the one or more textured surfaces includes a plurality of closely spaced continuous protrusions.
The invention provides a composite bone graft where the continuous protrusions include a cross-section having one or more shapes selected from the following: irregular; triangular, square, rectangular, and curved.
The invention further provides a composite bone graft where the plurality of continuous protrusions are sized to be in a range of greater than or equal to about 1.5 mm in length; 0.5 to about 10.0 mm in width and 0.1 to about 5.0 mm in depth.
The invention provides a composite bone graft where the plurality of closely spaced continuous protrusions are spaced from about 0.0 to about 3.0 mm apart.
The invention provides a composite bone graft where the plurality of protrusions are spaced from about 0.1 to about 2.0 mm apart.
The invention also provides a composite bone graft where the plurality of protrusions are spaced about 0.5 mm apart.
The invention provides a method for restoring vertical support of the posterior and/or anterior column by implanting a composite bone graft including two or more distinct bone portions held together by one or more connectors, at a site in a patient.
The invention provides a composite bone graft containing two or more connected bone portions, where the composite bone graft has a plurality of closely spaced protrusions on one or more surfaces thereof, where the protrusions are continuous protrusions, discrete protrusions, or a combination thereof.
The invention provides a composite bone graft where the plate-like cortical and/or cancellous bone portions are continuous bone portions and/or discontinuous bone portions.
The invention provides a composite bone graft including one or more discontinuous bone portions.
The invention provides a composite bone graft including one or more discontinuous, demineralized cortical bone portions.
The invention provides a composite bone graft including one or more discontinuous, demineralized cancellous bone portions.
The invention further provides a composite bone graft where one or more continuous or discontinuous cancellous bone portions, (continuous or discontinuous and/or demineralized)includes one or more therapeutically beneficial substances including but not limited to, for example, one or more of the following: osteoinductive substances, osteoconductive substances, and pharmaceutically active agents. Such therapeutically beneficial substances may optionally be provided with a carrier. Suitable osteoinductive substances include but are not limited to, for example, autograft bone; allograft bone; Grafton(trademark) produced by Osteotech; DynaGraft(trademark); demineralized cortical bone; demineralized cancellous bone; collagen including one or more growth factors including for example Novus(trademark) produced by Stryker Biotech; collagen including demineralized bone including for example DynaGraft(trademark); cancellous bone; cortical bone; OpteoForm(trademark) produced by the University of Florida; OsteoFill(trademark) produced by the University of Florida; and growth factors including for example bone morphogenic protein, and transforming growth factor-xcex2. Suitable osteoconductive substances include but are not limited to, for example, hydroxyapitate; collagen; any biocompatible matrix material including for example, polymeric matrix materials, bioglass, bioceramics, resorbable Biomaterials; bioabsorbable polymers; a plastic matrix; stainless steel; titanium; cobalt-chromium-molybdenum alloy matrix; and substances including hydroxyapitate, including for example, Osteoset(trademark) produced by Wright Medical. Suitable pharmaceutically active agents include but are not limited to, for example, growth factors including for example bone growth factors including for example bone morphogenic protein, and transforming growth factor-xcex2; chemotherapeutic agents; anti-inflammatory agents; and antibiotics.
The invention provides a composite bone graft where one or more continuous or discontinuous cancellous bone portions are demineralized and include one or more therapeutically beneficial substances.
The invention provides a composite bone graft where one or more discontinuous cortical bone portions, include one or more therapeutically beneficial substances.
The invention further provides a composite bone graft where one or more discontinuous cortical bone portions are demineralized and include one or more therapeutically beneficial substances.
The invention also provides a composite bone graft including a two or more distinct bone portions held together by one or more connectors, where the composite bone graft includes two diametrically opposing chamfered edges, one provided along the length of the graft at its top edge and the other provided along the length of the graft at its bottom edge, such that the chamfered edges are diametrically opposing.
The invention further provides a composite bone graft including two or more distinct interlocking cortical bone portions.
The invention provides a composite bone graft including two or more distinct interlocking bone portions, where the interlocking bone portions are self-locking.
The invention also provides a composite bone graft including two or more distinct interlocking bone portions, where the interlocking bone portions are locked with one or more locking pins.
The invention further provides a composite bone graft where bone portions are locked with one or more locking pins entirely or partially traversing a dimension of the composite bone graft.
The invention provides an interlocking composite bone graft where each complementary bone portion is provided with a discrete or continuous interlocking pattern.
The invention also provides an interlocking composite bone graft including two or more distinct adjacent bone portions where adjacent bone portions are configured to interlock with each other, and one or more bone pins partially or entirely traversing a dimension of the graft, where the dimension of the graft is the length, width, or height of the graft.
The invention provides an interlocking composite bone graft including two or more distinct adjacent bone portions where adjacent bone portions are configured to interlock with each other.
The invention provides a composite bone graft including two or more distinct adjacent interlocking bone portions where adjacent bone portions include complementary peg-like protrusions and corresponding depressions, such that the protrusions and depressions provide an interlocking fit between the bone portions.